This invention pertains to a machine for applying a clip to a socket imbedded within a tie and positioned at a side of a rail.
For many years, United States railroads have utilized rails mounted on wooden ties, with rail anchors associated with the rail where needed and with the rail anchors being mounted to extend transverse to the length of the rail and being set and applied by movement and forces applied transverse to the length of the rail. Additionally, tie plates have been positioned between the wooden tie and the rail and with spikes driven into the tie to secure the rail and tie plate to the tie.
In Canada, concrete ties are used wherein clips are associated with sockets cast into the concrete tie and are positioned to overlie the flanges of the rail base to hold the rail and tie in association. Normally, a pair of clips is associated with each rail at either side thereof and at one tie, with the clips being manually set and then forcefully applied, previously by use of a sledge hammer.
Machines, such as that described in U.S. Pat. No. 4,068,593, issued Jan. 17, 1978 to Leeves, have been developed which have the capability of applying either a single clip to one side of the rail or simultaneously applying clips to both sides of a single rail.
However, these machines have not provided any means for determining when the clip is properly driven and fully seated. The Leeves machine, for example, has a clip driving arm which includes an extension that interacts with the socket to stop the arm at a predetermined point, but this does not guarantee that the clip will not be overdriven due to manufacturing differences between sockets or clips.